SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '70a55f769b6529371bb005de32f7238cafe556374487f8663d77744dcdc78833' 
  AND token = 'gaV1lLBKlFMVJdnrw2RMIYiY2l3EoBjziS9dYgme+wI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}